Encapsulated integrated waveguide

Abstract

The present disclosure relates to packaged integrated waveguides. A method of manufacturing a packaged semiconductor device includes forming an assembly by coupling a semiconductor die and an antenna with the aid of a substrate, contacting at least a portion of a first surface of the antenna with a conformal structure, and encapsulating the assembly with an encapsulant such that the at least a portion of the first surface of the antenna contacted by the conformal structure is not encapsulated with the encapsulant.

Description

Technical Field

[0001] This disclosure generally relates to semiconductor device packaging, and more specifically to semiconductor devices having packaged integrated waveguides. Background Technology

[0002] Today, there is a growing trend to include radar systems in vehicles such as cars, trucks, and buses to provide drivers with enhanced awareness of objects around their vehicles. When a vehicle approaches an object (e.g., other cars, pedestrians, or obstacles), or when an object approaches the vehicle, the driver cannot always detect the object and take the necessary intervention to avoid a collision. Automotive radar systems installed in vehicles can detect the presence of objects, including other vehicles nearby, and provide the driver with timely information, enabling them to take possible interventions. However, such automotive radar systems can significantly impact vehicle costs. Summary of the Invention

[0003] According to one embodiment, a method of manufacturing a packaged semiconductor device includes:

[0004] Components are formed by connecting semiconductor dies and antennas using a substrate;

[0005] At least a portion of the first surface of the antenna is brought into contact with the conformal structure; and

[0006] The component is encapsulated by an encapsulation body, wherein at least a portion of the first surface of the antenna in contact with the conformal structure is not encapsulated by the encapsulation body.

[0007] In some embodiments, the method further includes removing the conformal structure to form an air cavity configured as a waveguide over the exposed portion of the first surface of the antenna.

[0008] In some embodiments, the method further includes forming a conductive layer on the sidewall of the air cavity, the conductive layer being coupled to a ground power supply terminal of the antenna.

[0009] In some embodiments, the waveguide dimensions are configured for propagating 77 GHz signals.

[0010] In some implementations, the method further includes:

[0011] Provides an extended waveguide structure with an extended air cavity; and

[0012] The extended waveguide structure is attached to at least a portion of the top surface of the encapsulation assembly, and the extended air cavity is arranged co-located with the air cavity such that the extended waveguide is formed above the exposed portion of the first surface of the antenna.

[0013] In some embodiments, providing the extended waveguide structure further includes:

[0014] The extended waveguide structure is formed using an injection molding process, the extended waveguide structure comprising a molding compound material surrounding the extended air cavity;

[0015] A conductive layer is formed on the sidewall of the expanded air cavity; and

[0016] When the extended waveguide structure is attached to at least a portion of the top surface of the encapsulation assembly, the conductive layer is connected to the ground power terminal of the antenna structure.

[0017] In some embodiments, the extended waveguide structure includes a heat sink that is in thermal contact with the back side of the semiconductor die when the extended waveguide structure is attached to at least a portion of the top surface of the encapsulation assembly.

[0018] In some embodiments, the substrate is a preformed or built-in substrate including a redistribution layer for connecting the semiconductor die and the antenna.

[0019] In some embodiments, the method further includes attaching solder balls to the bottom side of the substrate for electrical connection to a printed circuit board.

[0020] According to another embodiment, a packaged semiconductor device includes:

[0021] Component, the component includes:

[0022] A semiconductor die having an active surface and a back surface;

[0023] An antenna having a first primary surface and a second primary surface; and

[0024] A substrate configured to electrically connect bonding pads on the active surface of the semiconductor die to terminals on the first main surface of the antenna.

[0025] An encapsulation that encapsulates a portion of the component; and

[0026] An air cavity is formed in the encapsulation that exposes at least a portion of the second main surface of the antenna.

[0027] In some embodiments, the air cavity is formed by means of a membrane-assisted molding process.

[0028] In some embodiments, the substrate is a preformed or built-in substrate including a redistribution layer for connecting the bonding pads on the active surface of the semiconductor die to the terminals on the first main surface of the antenna.

[0029] In some embodiments, the packaged semiconductor device further includes a conductive layer formed on the sidewall of the air cavity, the conductive layer being coupled to the ground power supply terminal of the antenna.

[0030] In some embodiments, the packaged semiconductor device further includes an extended waveguide structure attached to at least a portion of the top surface of the encapsulation assembly, the extended waveguide structure including an extended air cavity arranged co-located with the air cavity, such that the extended waveguide is formed above the exposed portion of the second main surface of the antenna.

[0031] In some embodiments, the extended waveguide structure is formed using an injection molding process, and the extended waveguide structure includes a molding compound material surrounding the extended air cavity.

[0032] In some implementations, the extended air cavity has a width of approximately 2 millimeters and is configured for 77 GHz operation.

[0033] In some embodiments, the extended waveguide structure further includes a heat sink arranged co-located with the semiconductor die, the heat sink being in thermal contact with the back surface of the semiconductor die.

[0034] According to another embodiment, a method of manufacturing a packaged semiconductor device includes:

[0035] Components are formed by connecting semiconductor dies and antennas using a substrate;

[0036] At least a portion of the first surface of the antenna is brought into contact with the conformal structure; and

[0037] The component is encapsulated with an encapsulation body, such that an air cavity is formed within the encapsulation body that exposes at least a portion of the first surface of the antenna.

[0038] In some embodiments, the substrate is a preformed or built-in substrate including a redistribution layer for connecting bonding pads on the active surface of the semiconductor die to terminals on the second surface of the antenna.

[0039] In some embodiments, the method further includes attaching an extended waveguide structure to at least a portion of the top surface of the encapsulation assembly, the extended waveguide structure including an extended air cavity arranged co-located with the air cavity, such that the extended waveguide is formed above the exposed portion of the first main surface of the antenna. Attached Figure Description

[0040] The invention is illustrated by way of example and is not limited to the drawings, in which similar reference numerals indicate similar elements. Elements in the drawings are shown for simplicity and clarity, and these elements are not necessarily drawn to scale.

[0041] Figures 1-4 A simplified cross-sectional view illustrates an example packaged semiconductor device with integrated waveguides at different manufacturing stages according to an embodiment.

[0042] Figures 5-8 A simplified cross-sectional view illustrates an example packaged semiconductor device with an alternative substrate structure at different manufacturing stages according to an embodiment.

[0043] Figure 9 An example packaged semiconductor device having an extended waveguide structure during the manufacturing stage is shown in plan view according to an embodiment.

[0044] Figures 10-11 A simplified cross-sectional view is shown according to an embodiment during the manufacturing stage. Figure 9 Examples of packaged semiconductor devices along line AA.

[0045] Figure 12 An example packaged semiconductor device having an extended waveguide structure and a heat sink during the manufacturing stage is shown in plan view according to an embodiment.

[0046] Figures 13-14 A simplified cross-sectional view is shown according to an embodiment during the manufacturing stage. Figure 12 Examples of packaged semiconductor devices along the BB line. Detailed Implementation

[0047] Typically, packaged semiconductor devices with integrated waveguides are provided. The assembly, formed from a semiconductor die coupled to an antenna via a substrate, is partially encapsulated by an encapsulation. An air cavity within the encapsulation formed above the antenna is configured as a waveguide, thereby allowing efficient propagation (e.g., transmission and / or reception) of radar (e.g., WWWave) signals. The waveguide can be augmented using extended waveguide structures, demonstrating greater tuning capability for transmitting / receiving radar signals. By integrating the waveguide into / on the package, the required applied board space is minimized, and the overall cost is significantly reduced.

[0048] Figures 1-4 A simplified cross-sectional view illustrates an example packaged semiconductor device having an integrated waveguide 100 at different manufacturing stages according to an embodiment.

[0049] Figure 1 A simplified cross-sectional view illustrates the manufacturing stages of a packaged semiconductor device 100, including a semiconductor die 102 positioned on a substrate 108 to form an assembly and antennas 104-106. In this example, the packaged semiconductor device 100 can be characterized as a signal processing transceiver device, where one antenna is used to transmit signals and the other antenna is used to receive signals.

[0050] As in Figure 1The semiconductor die 102 depicted has an active surface (e.g., a main surface having a circuit system) and a back surface (e.g., a main surface opposite the active surface). The semiconductor die 102 includes bonding pads 110-112 at the active surface, configured for connection to antennas 104-106 via a substrate 108. In this embodiment, conductive pillars (e.g., copper pillars, nanotubes, solder bumps) 114-116 are used to connect the bonding pads 110-112 to corresponding bonding terminal pads on the substrate 108. In some embodiments, a resolderable material (e.g., solder) 115 may cover at least a portion of the conductive pillars 114-116 to facilitate electrical connection to the substrate 108. The semiconductor die 102 may be formed of any suitable semiconductor material, such as silicon, germanium, gallium arsenide, gallium nitride, etc. Semiconductor die 102 may additionally include any digital circuit, analog circuit, RF circuit, memory, signal processor, MEMS, sensor, and combination thereof.

[0051] As in Figure 1 As shown, antennas 104-106 each have a first main surface (e.g., a downward-facing main surface) and a second main surface (e.g., an upward-facing main surface opposite to the first main surface). Each of antennas 104-106 includes terminals 119 and 121 at the first main surface, which are configured for connection to a semiconductor die 102 via a substrate 108. In this embodiment, conductive posts 118 and 120 are used to connect terminals 119 and 121 to corresponding bonding terminal pads on the substrate 108.

[0052] The substrate 108 is a preformed substrate including a redistribution layer. The substrate 108 includes an insulating material 122, bonding terminal pads 124 on a first main surface, ball terminal pads 126 on a second main surface, and conductive traces 128-134 interconnecting the bonding terminal pads 124 and the ball terminal pads 126. During this manufacturing stage, the semiconductor die 102 and antennas 104-106 are attached to the substrate 108 to form an assembly. Conductive posts 114, 116, 118, and 120 are used to form electrical connections between the semiconductor die 102, antennas 104-106, and the substrate 108 of the assembly.

[0053] Figure 2 A simplified cross-sectional view is shown, including portions encapsulated with an encapsulant (e.g., a molding compound). Figure 1The subsequent manufacturing stage of the packaged semiconductor device 100 involves a film-assisted molding (FAM) tool 202 contacting a conformal structure (e.g., a film) 204 on the assembly formed by attaching the semiconductor die 102 and antennas 104-106 to a substrate 108. The conformal structure 204 conforms to the shape of the FAM tool 202 and contacts a predetermined portion of the second primary surface of the antennas 104-106. The encapsulation 206 is formed by substantially encapsulating the assembly with a molding compound, exposing (e.g., without encapsulation) the predetermined portion contacted by the conformal structure.

[0054] Figure 3 A simplified cross-sectional view is shown, including... Figure 2 The subsequent manufacturing stage of the packaged semiconductor device 100, which includes some of the packaged components, involves removing the conformal structure to form air cavities 306-308 of waveguides 318-320 configured above the exposed portions of the second main surfaces of antennas 104-106. The dimensions (e.g., width, length) of waveguides 318-320 can be configured to propagate signals having a desired wavelength (e.g., radar signals of 76-81 GHz). For example, waveguide 318 can be configured to propagate (e.g., transmit) radar signals with a frequency of 77 GHz. Because a 77 GHz signal has a wavelength of approximately 4 mm, waveguide 318 is configured to have a width dimension 322 of approximately 2 mm, or half the desired wavelength.

[0055] A conductive layer (e.g., metal or other conductive material) is formed on the sidewalls 310 of air cavity 306 and 312 of air cavity 308. The conductive layer formed on sidewalls 310-312 is connected to the power terminals of antennas 104-106 at junctions 314-316. In this embodiment, the conductive layer is a metal layer formed on sidewalls 310-312 that is connected to the ground power terminals of antennas 104-106. In other embodiments, the conductive layer formed on sidewalls 310-312 may be connected to other power terminals (e.g., operating voltage sources) of antennas 104-106. In this embodiment, a photolithography process is used to isolate the sidewalls of air cavities 306-308 using a mask 302, and a deposition process is used to sputter and deposit a conductive coating 304 on the isolated sidewalls. In other embodiments, other techniques may be used to form a conductive coating or layer on the sidewalls of cavities 306-308.

[0056] Figure 4A simplified cross-sectional view illustrates a subsequent manufacturing stage of the packaged semiconductor device 100, including an attached conductive ball connector (e.g., solder ball) 402. In this manufacturing stage, the ball connector 402 is attached to the ball terminal pad 126 using known techniques and materials. Alternatively, the ball connector 402 can be any suitable conductive structure, such as a gold pillar, copper pillar, etc., to electrically connect, for example, conductive features of the packaged semiconductor device 100 to a printed circuit board.

[0057] Figures 5-8 A simplified cross-sectional view illustrates an example packaged semiconductor device 500 having an alternative substrate structure at different manufacturing stages according to an embodiment.

[0058] Figure 5 A simplified cross-sectional view illustrates the manufacturing stages of an alternative packaged semiconductor device 500 including partially encapsulated components. In this stage, a semiconductor die 102 and antennas 104-106 are configured to form an assembly on a carrier 510 and partially encapsulated using an encapsulator (e.g., a molding compound) for FAM (Fan-Ampere Atomization) processing. The semiconductor die 102 has its active surface facing downwards at a first region of an adhesive layer 508 on the carrier 510, and the antennas 104-106 have their first main surfaces facing downwards at second and third regions of the adhesive layer 508 on the carrier 510, respectively. After the semiconductor die 102 and antennas 104-106 are placed, a FAM tool 502 contacts a conformal structure (e.g., a film) 504 on the assembly formed by the semiconductor die 102 and antennas 104-106 through the adhesive layer 508 on the carrier 510. The conformal structure 504 conforms to the shape of the FAM tool 502 and contacts a predetermined portion of the second main surface of the antennas 104-106. Encapsulation 506 is formed by substantially encapsulating the assembly with a molding compound, exposing (e.g., without encapsulation) predetermined portions contacted by the conformal structure. The bonding pads 110-112 of the semiconductor die 102 and the terminals 119 and 121 of the antenna 104-106 will be connected to the conductive ball connector by means of a built-in substrate formed later in the manufacturing process.

[0059] Figure 6 A simplified cross-sectional view is shown, including... Figure 5This is a subsequent manufacturing stage of the packaged semiconductor device 500, which includes a portion of the packaged components. In this stage, the conformal structure is removed, thereby forming air cavities 606-608 configured to be above exposed portions of the second main surfaces of antennas 104-106, consisting of waveguides 618-620. The dimensions (e.g., width, length) of air cavities 606-608 can be configured for propagating signals with a desired wavelength. Conductive (e.g., metallic) layers are formed on the sidewalls 610 of air cavity 606 and 612 of air cavity 608. The conductive layers formed on sidewalls 610-612 are coupled to power terminals (e.g., ground power or other voltage power supplies) of antennas 104-106 at junctions 614-616. In this embodiment, a photolithography process is used to isolate the sidewalls of air cavities 606-608 using a mask 602, and a deposition process is used to sputter and deposit a conductive coating 604 on the isolated sidewalls. In other embodiments, other techniques may be used to form a conductive coating or layer on the sidewalls of cavities 606-608.

[0060] Figure 7 A simplified cross-sectional view is shown, including a substrate 702. Figure 6 This is a subsequent manufacturing stage of the partially encapsulated semiconductor device 500. In this stage, a substrate 702 is formed using an in-situ process in which insulating and conductive layers are patterned and continuously in-situ to form interconnected redistribution layers. The semiconductor die 102 is interconnected with antennas 104-106 via the completed substrate 702. The in-situ substrate 702 includes bonding terminal pads 704 formed on a first main surface, ball terminal pads 706 formed on a second main surface, and conductive traces 708-714 interconnecting the bonding terminal pads 704 and 706. The bonding terminal pads 704 form electrical connections with bonding pads 110-112 of the semiconductor die 102 and terminals 119 and 121 of the antennas 104-106.

[0061] Figure 8 A simplified cross-sectional view illustrates a subsequent manufacturing stage of the packaged semiconductor device 500, including an attached conductive ball connector (e.g., solder ball) 802. In this manufacturing stage, the ball connector 802 is attached to the ball terminal pad 706 using known techniques and materials. Alternatively, the ball connector 802 can be any suitable conductive structure, such as a gold pillar, copper pillar, etc., to electrically connect, for example, the conductive features of the packaged semiconductor device 500 to a printed circuit board.

[0062] Figures 9-11 The example packaged semiconductor device 900 having extended waveguide structures 902-904 at different manufacturing stages according to the embodiment is shown in plan view and cross-sectional view.

[0063] Figure 9 A plan view illustrates an example packaged semiconductor device 900 having extended waveguide structures 902-904 during the manufacturing stage according to an embodiment. The diagram shows a packaged semiconductor device 900 positioned as such... Figure 4 The extended waveguide structures 902-904 on the partially encapsulated assembly are depicted during the manufacturing stage. Here, the semiconductor die 102 is attached to the substrate 108 (for simplicity, the encapsulation 206 and antenna 104-antenna 106 are not shown). Figure 10 The figure shows a cross-sectional view of a packaged semiconductor device 900 with extended waveguide structures 902-904 taken along line AA.

[0064] Extended waveguide structures 902-904 include one or more air cavities 908 and 914 formed in respective rigid portions (e.g., cured molding compound) 906 and 912. In this embodiment, the one or more cavities 908 and 914 are formed in the molding compound portions 906 and 912 by means of an injection molding process. A conductive (e.g., metallic) layer is formed on sidewalls 910 and 916 of each of the one or more air cavities 908 and 914. In a subsequent stage, the conductive layer formed on the sidewalls 910 and 916 is coupled to the power supply terminals (e.g., ground power or other voltage power supply) of antenna 104-antenna 106.

[0065] Figure 10 A simplified cross-sectional view is shown according to an embodiment during the manufacturing stage. Figure 9 Example of a packaged semiconductor device along line AA. In this manufacturing stage, the packaged semiconductor device 900 includes a device positioned having, as in... Figure 4 The extended waveguide structures 902-904 on the partial encapsulation assembly 1000 of the ball connector 402 depicted herein. It should be noted that when the packaged semiconductor device 900 is configured with extended waveguide structures 902-904, the extended waveguide structures 902-904 can be omitted. Figure 3 The deposition steps described herein (e.g., a conductive layer on sidewalls 310-312). Adhesives 1002-1004 are applied to the sidewalls and shoulders of the respective air cavities 306-308. Adhesives 1002-1004 may be dispensed or applied as a film and may be conductive.

[0066] Figure 11 A simplified cross-sectional view is shown according to an embodiment during the subsequent manufacturing stage. Figure 9An example of a packaged semiconductor device is shown along line AA. At this stage, the packaged semiconductor device 900 includes extended waveguide structures 902-904 attached to a partial encapsulation assembly 1000. Conductive layers formed on the sidewalls 910 of air cavity 908 and 916 of air cavity 914 are coupled at junctions 1102-1104 to power terminals (e.g., ground power or other voltage power) of antennas 104-106. In some embodiments, adhesives 1002-1004 may be conductive adhesives extending to junctions 1102-1104 to couple the conductive layers formed on sidewalls 910 and 916 to the power terminals of antennas 104-106.

[0067] With extended waveguide structures 902-904 attached to the partial encapsulation assembly 1000, air cavities 908 and 914 are configured as extended waveguides 1106-1108 above the exposed portions of the second main surfaces of antennas 104-106. The dimensions (e.g., width, length) of extended waveguides 1106-1108 can be configured for propagating signals with a desired wavelength (e.g., radar signals). For example, extended waveguide 1106 can be configured for propagating (e.g., transmitting) radar signals with a frequency of 77 GHz. Because a 77 GHz signal has a wavelength of approximately 4 mm, extended waveguide 1106 is configured to have a width dimension 1110 of approximately 2 mm or half the desired wavelength.

[0068] Figures 12-14 The plan view and cross-sectional view illustrate an example packaged semiconductor device 1200 having extended waveguide structures 1202-1204 and a heat sink 1212 at different manufacturing stages according to an embodiment.

[0069] Figure 12 A plan view illustrates an example packaged semiconductor device 1200 having extended waveguide structures 1202-1204 and a heat sink 1212 during the manufacturing stage according to an embodiment. Figure 4 The extended waveguide structures 1202-1204 and the heat sink 1212 are partly encapsulated on the same manufacturing stage. Here, the semiconductor die 102 (not shown) is attached to the substrate 108 (for simplicity, the encapsulation 206 and antenna 104-antenna 106 are not shown). Figure 13 The figure shows a cross-sectional view of a packaged semiconductor device 1200 with extended waveguide structures 1202-1204 and a heat sink 1212, taken along line BB.

[0070] Extended waveguide structures 1202-1204 include one or more air cavities 1208 and 1214 formed in a rigid portion (e.g., a cured molding compound) 1206. In this embodiment, the one or more cavities 1208 and 1214 are formed in the molding compound portion 1206 by means of an injection molding process. A conductive (e.g., metallic) layer is formed on sidewalls 1210 and 1216 of each of the one or more air cavities 1208 and 1214. In a subsequent stage, the conductive layer formed on the sidewalls 1210 and 1216 is coupled to terminals of the antenna 104-antenna 106 (e.g., ground or other voltage power supply), and the main surface of the heat sink 1212 is in thermal contact with the back surface of the semiconductor die 102 (e.g., by means of a thermal interface material).

[0071] The heat spreader radiator 1212 is formed or press-fitted in the rigid portion 1206. In this embodiment, the radiator 1212 is at least partially encapsulated in the molding compound portion 1206 by means of an injection molding process. The radiator 1212 may be referred to as a flange configured for dissipating heat, a heat dissipation device, or an embedded coin. The radiator 1212 may be formed of copper, silver, aluminum, gold, other conductive materials, or combinations and alloys thereof. In some embodiments, the radiator 1212 may be formed of a composite material of multiple conductive materials.

[0072] Figure 13 A simplified cross-sectional view is shown according to an embodiment during the manufacturing stage. Figure 12 Example of a packaged semiconductor device along line BB. In this manufacturing stage, the packaged semiconductor device 1200 includes a device positioned having, as in... Figure 4 The ball connector 402 depicted in the illustration features an extended waveguide structure 1202-1204 and a heat sink 1212 on a portion of the encapsulation assembly 1300. In this embodiment, the back surface of the semiconductor die 102 is... Figure 2 The encapsulation steps described herein are then exposed. For example, the semiconductor die 102 may be formed to have a greater thickness, such that the conformal structure 204 also contacts the back surface of the semiconductor die 102, in addition to a predetermined portion of the second main surface of the antenna 104-antenna 106. It should be noted that when the packaged semiconductor device 1200 is configured with the extended waveguide structure 1202-extended waveguide structure 1204, the encapsulation steps described herein may be omitted. Figure 3The deposition steps depicted (e.g., conductive layers on sidewalls 310-312) are described. Adhesives 1302-1304 are applied to the sidewalls and shoulders of the respective air cavities 306-308, and a thermal interface (e.g., thermally conductive) material 1306 is applied to the back surface of the semiconductor die 102. Adhesives 1302-1304 and thermal interface material 1306 may be dispensed or applied as films. Adhesives 1302-1304 and thermal interface material 1306 may be formed from the same material having both adhesive and thermally conductive properties.

[0073] Figure 14 A simplified cross-sectional view is shown according to an embodiment during the subsequent manufacturing stage. Figure 9 An example of a packaged semiconductor device is shown along line AA. At this stage, the packaged semiconductor device 1200 includes extended waveguide structures (1202-1204) and a heat sink 1212 attached to a partial encapsulation assembly (1300). Conductive layers formed on the sidewalls 1210 of air cavity 1208 and 1216 of air cavity 1214 are coupled to the power terminals (e.g., ground power or other voltage power supply) of antenna 104-antenna 106 at junctions 1402-1404. In some embodiments, adhesives 1302-1304 may be conductive adhesives extending to junctions 1402-1404 to couple the conductive layers formed on sidewalls 1210 and 1216 to the power terminals of antenna 104-antenna 106.

[0074] With the extended waveguide structure attached to the partially encapsulated assembly, air cavities 1208 and 1214 are configured as extended waveguides 1406-1408 above the exposed portions of the second main surfaces of antennas 104-106. The dimensions (e.g., width, length) of extended waveguides 1406-1408 can be configured for propagating signals with a desired wavelength (e.g., radar signals). For example, extended waveguide 1406 can be configured for propagating (e.g., transmitting) radar signals with a frequency of 77 GHz. Because a 77 GHz signal has a wavelength of approximately 4 mm, extended waveguide 1406 is configured to have a width dimension of approximately 2 mm, or half the desired wavelength.

[0075] Typically, a method of manufacturing a packaged semiconductor device is provided, the method comprising forming an assembly by connecting a semiconductor die and an antenna via a substrate; contacting at least a portion of a first surface of the antenna with a conformal structure; and encapsulating the assembly with a molding compound, wherein at least a portion of the first surface of the antenna contacted by the conformal structure is not encapsulated with the molding compound. The method may further include removing the conformal structure to form an air cavity configured as a waveguide over an exposed portion of the first surface of the antenna. The method may further include forming a conductive layer on the sidewalls of the air cavity, the conductive layer being coupled to a ground power supply terminal of the antenna. The waveguide dimensions may be configured for propagating a 77 GHz signal. The method may further include providing an extended waveguide structure having an extended air cavity; and attaching the extended waveguide structure to at least a portion of the top surface of the encapsulated assembly, the extended air cavity being arranged co-located with the air cavity such that the extended waveguide is formed over an exposed portion of the first surface of the antenna. Providing an extended waveguide structure may further include forming the extended waveguide structure using an injection molding process, the extended waveguide structure including a molding compound material surrounding an extended air cavity; forming a conductive layer on the sidewalls of the extended air cavity; and connecting the conductive layer to a ground power terminal of the antenna structure when the extended waveguide structure is attached to at least a portion of the top surface of the encapsulation assembly. The extended waveguide structure may include a heat sink that is in thermal contact with the back side of the semiconductor die when the extended waveguide structure is attached to at least a portion of the top surface of the encapsulation assembly. The substrate may be a preformed or built-in substrate including a redistribution layer for connecting the semiconductor die and the antenna. The method may further include attaching solder balls to the bottom side of the substrate for electrical connection to a printed circuit board.

[0076] In another embodiment, a packaged semiconductor device is provided comprising a semiconductor die having an active surface and a back surface; an antenna having a first main surface and a second main surface; and a substrate configured to electrically connect bonding pads on the active surface of the semiconductor die to terminals on the first main surface of the antenna; an encapsulation body encapsulating a portion of the assembly; and an air cavity formed in the encapsulation body exposing at least a portion of the second main surface of the antenna. The air cavity may be formed by means of a film-assisted molding process. The substrate may be a preformed or built-in substrate including a redistribution layer for connecting bonding pads on the active surface of the semiconductor die to terminals on the first main surface of the antenna. The packaged semiconductor device may further include a conductive layer formed on the sidewalls of the air cavity, the conductive layer being coupled to a ground power supply terminal of the antenna. The packaged semiconductor device may further include an extended waveguide structure attached to at least a portion of the top surface of the encapsulation assembly, the extended waveguide structure including an extended air cavity arranged co-located with the air cavity such that the extended waveguide is formed above the exposed portion of the second main surface of the antenna. The extended waveguide structure can be formed using an injection molding process. The extended waveguide structure includes a molding compound material surrounding an extended air cavity. The extended air cavity may have a width of approximately 2 mm and can be configured for 77 GHz operation. The extended waveguide structure may additionally include a heat sink arranged co-located with the semiconductor die, the heat sink being in thermal contact with the back surface of the semiconductor die.

[0077] In yet another embodiment, a method of manufacturing a packaged semiconductor device is provided, the method comprising forming an assembly by connecting a semiconductor die and an antenna via a substrate; contacting at least a portion of a first surface of the antenna with a conformal structure; and encapsulating the assembly with an encapsulation such that an air cavity is formed within the encapsulation exposing at least a portion of the first surface of the antenna. The substrate may be a preformed or built-in substrate including a redistribution layer for connecting bonding pads on an active surface of the semiconductor die to terminals on a second surface of the antenna. The method may further include attaching an extended waveguide structure to at least a portion of the top surface of the encapsulated assembly, the extended waveguide structure including an extended air cavity arranged co-located with the air cavity, such that the extended waveguide is formed above an exposed portion of the first main surface of the antenna.

[0078] Now, it is important to understand packaged semiconductor devices with integrated waveguides. An assembly formed from a semiconductor die coupled to an antenna via a substrate is partially encapsulated by an encapsulation. An air cavity within the encapsulation formed above the antenna is configured as a waveguide, thereby allowing efficient propagation (e.g., transmission and / or reception) of radar (e.g., WWWave) signals. The waveguide can be augmented using extended waveguide structures, demonstrating greater tuning capability for transmitting / receiving radar signals. By integrating the waveguide into / on the package, the required applied board space is minimized, and the overall cost is significantly reduced.

[0079] The terms “front,” “back,” “top,” “bottom,” “on,” “under,” etc., as used in this specification and claims (if applicable), are for descriptive purposes and are not necessarily used to describe permanent relative positions. It should be understood that such terms are interchangeable where appropriate, such that embodiments of the invention described herein can be operated, for example, in orientations other than those shown or otherwise described herein.

[0080] While the invention has been described herein with reference to specific embodiments, various modifications and changes may be made without departing from the scope of the invention as set forth in the claims below. Therefore, the specification and drawings should be considered illustrative rather than restrictive, and all such modifications are intended to be included within the scope of the invention. It is not intended that any benefit, advantage, or solution to the problem described herein with reference to specific embodiments be construed as a critical, necessary, or essential feature or element of any or all claims.

[0081] Furthermore, as used herein, the term "a" is defined as one or more. Moreover, the use of introductory phrases such as "at least one" and "one or more" in the claims should not be construed as implying that any particular claim containing such an introduced element is limited to an invention containing only one such element, even when the same claim includes the introductory phrase "one or more" or "at least one" and an indefinite article such as "a". The same applies to the use of definite articles.

[0082] Unless otherwise stated, terms such as “first” and “second” are used to distinguish, arbitrarily, the elements described by such terms. Therefore, these terms are not necessarily intended to indicate the temporal or other priorities of such elements.

Claims

1. A method for manufacturing a packaged semiconductor device, characterized in that, The method includes: Components are formed by connecting semiconductor dies and antennas using a substrate; At least a portion of the first surface of the antenna is brought into contact with the conformal structure; The component is encapsulated by an encapsulation body, wherein at least a portion of the first surface of the antenna in contact with the conformal structure is not encapsulated by the encapsulation body; Remove the conformal structure to form an air cavity configured as a waveguide above the exposed portion of the first surface of the antenna; and A conductive layer is formed on the sidewall of the air cavity.

2. The method according to claim 1, characterized in that, In addition, including: Provides an extended waveguide structure with an extended air cavity; and The extended waveguide structure is attached to at least a portion of the top surface of the encapsulated component, and the extended air cavity is arranged co-located with the air cavity such that the extended waveguide is formed above the exposed portion of the first surface of the antenna.

3. The method according to claim 2, characterized in that, The extended waveguide structure further includes: The extended waveguide structure is formed using an injection molding process, the extended waveguide structure comprising a molding compound material surrounding the extended air cavity; A conductive layer is formed on the sidewall of the expanded air cavity; and When the extended waveguide structure is attached to at least a portion of the top surface of the encapsulated component, the conductive layer is connected to the ground power terminal of the antenna.

4. The method according to claim 2, characterized in that, The extended waveguide structure includes a heat sink that is in thermal contact with the back side of the semiconductor die when the extended waveguide structure is attached to at least a portion of the top surface of the encapsulated component.

5. A packaged semiconductor device, characterized in that, include: Component, the component includes: A semiconductor die having an active surface and a back surface; An antenna having a first primary surface and a second primary surface; and A substrate configured to electrically connect bonding pads on the active surface of the semiconductor die to terminals on the first main surface of the antenna. An encapsulation that encapsulates a portion of the component; An air cavity formed within the encapsulation that exposes at least a portion of the second main surface of the antenna; and A conductive layer is formed on the sidewall of the air cavity.

6. The packaged semiconductor device according to claim 5, characterized in that, The substrate is a preformed or built-in substrate including a redistribution layer for connecting the bonding pads on the active surface of the semiconductor die to the terminals on the first main surface of the antenna.

7. The packaged semiconductor device according to claim 5, characterized in that, Additionally, it includes an extended waveguide structure attached to at least a portion of the top surface of the encapsulated component, the extended waveguide structure including an extended air cavity arranged co-located with the air cavity, such that the extended waveguide is formed above the exposed portion of the second main surface of the antenna.

8. A method for manufacturing a packaged semiconductor device, characterized in that, The method includes: Components are formed by connecting semiconductor dies and antennas using a substrate; At least a portion of the first surface of the antenna is brought into contact with the conformal structure; The component is encapsulated with an encapsulation body, such that an air cavity is formed within the encapsulation body that exposes at least a portion of the first surface of the antenna; and A conductive layer is formed on the sidewall of the air cavity.

9. The method according to claim 8, characterized in that, Additionally, it includes attaching an extended waveguide structure to at least a portion of the top surface of the encapsulated component, the extended waveguide structure including an extended air cavity arranged co-located with the air cavity, such that the extended waveguide is formed above the exposed portion of the first surface of the antenna.

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